CVE-2026-45799
HighCVSS 7.5Exploitation Probability (EPSS)
Elevated risk54th percentile - higher than 54% of all known CVEs
Summary
Vulnerability in Wire library (gRPC/protobuf) for Android, Kotlin, Swift, and Java. In versions prior to 6.3.0 and 7.0.0-alpha03, skipGroup() methods do not validate that LENGTH_DELIMITED field length is non-negative, potentially causing ArrayIndexOutOfBoundsException and crashing services decoding untrusted data.
Risk Assessment
Risk of service crashes in applications using Wire to decode protobuf from untrusted sources, potentially leading to application downtime.
Recommendation
Update Wire library to version 6.3.0 or 7.0.0-alpha03. Avoid decoding untrusted protobuf data without validation.
Other vulnerabilities in Wire
See all- CVE-2026-61695High
Wire provides gRPC and protocol buffers for Android, Kotlin, Swift, and Java. Prior to 6.4.1 and 7.0.0-alpha04, Wire's Swift runtime ProtoReader.skipGroup(expectedEndTag:unknownFieldsWriter:) accepts a negative length for a LENGTH_DELIMITED field inside an unknown START_GROUP field. ProtoReader.readData() forwards the negative count to ReadBuffer.readData(count:), whose upper-bound-only check permits the value to reach Foundation Data(bytes:count:) and trigger an unrecoverable process trap instead of a catchable ProtoDecoder.Error. Any Swift process decoding untrusted protobuf bytes can be crashed without authentication, user interaction, or knowledge of the target schema. This issue is fixed in versions 6.4.1 and 7.0.0-alpha04.
- CVE-2026-63126High
Wire (gRPC/protobuf for Android, Kotlin, Swift, and Java) before 6.4.5 and 7.0.0-alpha04 does not consistently validate attacker-controlled lengths against the current logical message boundary. In Kotlin, decoding paths (e.g., ProtoAdapter.decode, internalNextLengthDelimited, ReadBuffer.readVarint, ProtoDecoder.decodeSizeDelimited) can cross logical boundaries, perform pointer arithmetic, or reserve excessive memory. An attacker supplying malformed protobuf bytes can cause unchecked exceptions, traps, out-of-bounds behavior, or excessive allocation, resulting in denial of service.
Original NVD description (English source)
Wire provides gRPC and protocol buffers for Android, Kotlin, Swift, and Java. Prior to 6.3.0 and 7.0.0-alpha03, ByteArrayProtoReader32.skipGroup() and ProtoReader.skipGroup() in wire-runtime do not validate that a LENGTH_DELIMITED field length is non-negative before skip(), allowing a crafted protobuf varint encoding -128 as a signed Int to make skip(-128) move the internal position negative and make the next readByte() throw ArrayIndexOutOfBoundsException instead of the documented IOException or ProtocolException, which can crash services using ProtoAdapter.decode(byte[]) on untrusted payloads. This issue is fixed in versions 6.3.0 and 7.0.0-alpha03.
Vulnerability data from NVD (NIST) · CISA KEV · EPSS